The present description relates, in general, to vehicle body structures and, particularly, to energy absorbing vehicle body structures.
Automobile and other vehicle bodies are typically formed of a number of metal and/or plastic components and body panels that are mounted on and connected to underlying rigid frame members. The components and body panels can be typically attached to the frame members by various attachment brackets which take a variety of different forms depending upon the location and shape of the associated components and body panels.
Such attachment brackets are designed to have a required amount of strength and stiffness so as to securely and non-movably affix the attached component or body panel to the underlying frame structure despite the vibrations and forces encountered during vehicle operation.
At the same time, such attachment brackets as well as the components and body panels themselves can be designed with energy absorption features so as to absorb impact energy exerted on the components and body panels and attachment brackets during a vehicle collision or impact with a stationary object or pedestrian. Such energy absorption is intended to minimize injury to the occupants of the vehicle as well as any pedestrians impacting with the vehicle.
Thus, there exists a need to create vehicle component and body panel attachment brackets which provide the requisite strength and stiffness for the attached component and vehicle body panels and at the same time are capable of deformation to absorb impact energy in the event the portion of the component or body panel attached by the attachment bracket to the underlying frame structure is impacted an external object, such as a pedestrian.
In particular, a vehicle headlamp housing is affixed to one or more surrounding vehicle components, including a vehicle fender, vehicle frame, radiator strap, etc. It is desirable that the headlamp housing has sufficient stiffness in all “x”, “y”, and “z” axes so as to be incapable of movement when the vehicle is at rest and during vehicle operation. To this end, as shown in FIGS. 1-3, an attachment bracket carried on the headlamp housing has a vertically extending wall which terminates in an angularly or perpendicularly disposed upper flange. An aperture in the upper flange receives a fastener for attaching the attachment bracket to an adjacent vehicle component, such as the vehicle fender inner flange.
As seen in FIGS. 2 and 3, the attachment bracket includes one or at least two vertically extending, laterally spaced ribs between the wall and the upper end flange. The ribs are generally oriented in the longitudinal vehicle direction so as to provide stiffness to the attachment bracket and thereby resist movement of the attachment bracket and the headlamp housing along one axis, such as in a horizontal or longitudinal direction, when the vehicle is stationary or during vehicle operation.
However, the stiffness and strength provided by the one or more ribs on the attachment bracket, while providing the requisite stiffness to horizontal movement of the attachment bracket and the attached headlamp housing, results in a substantially immovable structure which does not significantly yield when an impact force, such as a pedestrian striking the fender of the vehicle during a collision between the vehicle and the pedestrian, in the area of the attachment bracket thereby imposing a vertical load on the attachment bracket. The stiffness of the attachment bracket creates the substantially immovable structure which is difficult to deform due to high reaction forces, thereby creating a greater potential for pedestrian injury.